简介：Ascorbateperoxidase,ahaemprotein(EC1.11.1.11),efficientlyscavengeshydrogenperoxide(H2O2)incytosolandchloroplastsofplants.Inthisstudy,afulllengthcodingsequenceofthylakoid-boundascorbateperoxidasecDNA(TatAPX)wasclonedfromadroughttolerantwheatcultivarC306.HomologymodelingoftheTatAPXproteinwasperformedbyusingthetemplatecrystalstructureofchloroplasticascorbateperoxidasefromtobaccoplant(PDB:1IYN).ThemodelstructurewasfurtherrefinedbymolecularmechanicsanddynamicmethodsusingvarioustoolssuchasPROCHECK,ProSAandVerify3D.ThepredictedmodelwasthentestedfordockingwithH2O2,thesubstrateforTatAPXenzyme.TheresultsrevealedthatArg233andGlu255inthepredictedactivesiteoftheenzymearetwoimportantaminoacidresiduesresponsibleforstronghydrogenbondingaffinitywithH2O2,whichmightplayanimportantroleinscavengingofH2O2fromtheplantsystem.